Using sql server 2019 I have a windows user and want to assign it to a database. but no mater which which windows user I use, I get an error
Create failed for User 'xxx-xxx\sysadmin'. 'xxx-xxx\sysadmin' is not a valid name because it contains invalid characters.
Where "xxx-xxx" is the machine name created by the datacenter.
It seems odd that I can't assign a windows user to the db. Any solutions?